FQXi researchers pride themselves on pushing the boundaries of what’s known—positing theories at the edge of what we can conceive. Unfortunately, this almost inevitably involves hypothesizing things that lie far beyond what can currently be tested. Many are waiting for results from the LHC or from some new telescope or the other to provide some evidence for or against their ideas. Still others can’t promise that their predictions can be falsified by any experiment currently envisaged. As such, theorists are often criticised for letting their ideas run wild. So it’s nice to see that one of FQX’s astronomers, Harvard’s Avi Loeb, is making an effort to go back and double check the observational evidence for a theoretical entity that seems to have transitioned from science fiction to science fact over the past decades: the black hole.

Chandra close up of Sgr A*

Black holes may have seemed wacky when they were first proposed, but they are now so firmly embedded in public consciousness that most current headlines referring to them do so metaphorically, usually to describe our dire financial straits—“Billions Go Down a Black Hole,” “Black Hole balance sheets,” “Budget leaves a Black Hole.” (Possibly there’s something weird physics-y time-travel effect happening with the second headline. As I access the page now, the news article is running with _tomorrow’s_ date.)

As far as black holes in physics are concerned, most assume they exist—some even producing simulations of what it would look like to fall into one. Every so often, though, physicists offer up controversial alternative interpretations to the evidence for black holes, including wormholes, stars built out of dark energy, or bubbles of exotic dark matter. So it’s worth seriously re-examining the evidence we have for the black hole at the center of our galaxy, as Loeb is doing.

In 2006, Loeb won an FQX grant to hunt for intelligent alien life. (You can read more about the search in “Eavesdropping on ET.”) Loeb and his colleagues have been busy releasing a bunch of papers, which have been popping up in the news over the past couple of weeks, talking about rogue black holes munching their way round the Milky Way. (Sometimes I wonder if Loeb chooses his research topics based on the plots of 1950’s B-movies. If his search for ET comes back with a warning about rampaging vertically-enhanced females, I will be very suspicious.)

Weak jokes aside, Loeb does great work and is aware of the importance of using the latest observational techniques to rigorously check what many take for granted, for instance, the existence of “event horizons”—the surfaces that are believed to surround black holes, beyond which light cannot escape. That’s something that New Scientist’s David Shiga picked up on when he eschewed writing about some of Loeb’s more headline-grabbing findings to report on his paper from March with Avery Broderick and Ramesh Narayan, reviewing our latest observations of Sagittarius A* (Sgr A*), the supermassive black-hole candidate at the center of our galaxy. Churning through the evidence, they conclude that it does appear to be a black hole shrouded by an event horizon, as commonly supposed. (For those who regard black holes and event horizons as mundane, Shiga points out that the observations don’t rule out the possibility that Sgr A* is a wormhole.)

It’s sobering to note that the earliest theoretical paper on event horizons that Loeb refers to in his paper was written as far back as 70 years ago, in 1939, by J. Robert Oppenheimer (yes, that J. Robert Oppenheimer) and his graduate student Hartland Snyder. Oppenheimer is now remembered as the “Father of the Atomic Bomb,” but he was also one of the first researchers to seriously look into whether the bizarre entities predicted by the equations of general relativity actually could exist. Looking for the root of the idea of black holes takes you back far further, to the eighteenth century and English geologist John Michell. (The image shows the title and an excerpt from his 1783 paper, which first described the concept of a black hole in Philosophical Transactions of the Royal Society of London. Photo courtesy of the Philosophical Transactions of the Royal Society of London, vol. 74, pp. 35. 1783.)

The moral of the story is clearly that for FQXers and others hoping for experimental or observational support for their ideas, patience—possibly stretching over centuries—is a virtue.

Finally, I can’t talk about black holes without mentioning the man whose name is almost synonymous with them, having laid much of the groundwork on the topic and famously losing a bet about the fate of information about things that fall into black holes. Stephen Hawking’s ill health has been in the news since he was rushed to Addenbrooke’s Hospital in Cambridge with a chest infection earlier this month. The thoughts of everyone at FQX are with him and his family, as we wish him a full recovery.

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The following site has a number of numerical renditions on how entering a black hole would visually appear.

http://jilawww.colorado.edu/~ajsh/insidebh/index.html


Lawrence B. Crowell

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One feature of black holes which stands out for me, are the jets of electrons shooting out the poles. Between them and the radiation which pours out of galaxies before falling into the black hole, much of the mass energy absorbed by a galaxy is accounted for. So rather than black holes being a dense object, or worm hole into another dimension, it seems they are possibly a gravitational storm that converts intergalactic gases into highly charged particles.

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It's guaranteed to blow your mind, whichever way you look at it. Spinning off in another galaxy...floating forever in zero gravity...always a favourite topic for anyone teaching children by the way. Send them to the very good http://www.rense.com/general72/size.htm to get them started on the concept of size, and watch their minds expand!

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Hi all ,

Dear Lawrence,thanks for this link ,it's well resumed on this website.

Personaly,I think what a Blak Hole is linked with the velocity of rotation of ultim coded sphere ,the spin of the Black Hole ,its mass ,its electric charge ,the sense ,the attraction ....all these systems are in correlation with spherization ,indeed ,the attraction of the black hole ,like our galaxy and its center,permits a balance of spherization with its sense of rotation (during expansion a sense ,during contraction the other sense ),the stars turn around this cenetr,the space decrease ,or will decrease if we consider our step of evolution in Time .

In this logic our Black Holes are balances ,balance points with the main field ,the main code of the sphere I think in the center .

The centers are the key and their codes and that everywhere in everything.

Perhaps the different kinds of Black Holes are different steps of evolution ,of evolution due to the relativistic perception.

The mass ,the sense ,the spin,the electric charge are perhaps in correlation with the time and its frequences of evolution ,like some different rules of attraction and repulsion during the time space evolution .In this logic ,It exists specific sequences ,series where spin mass and charge are variables .,perhaps the maximum volume after the expansion step have specific parameters where spin mass and el charge are balanced ,the contraction implies different parameters about mass el ch and spin ,the time can be insert with specific phases too.

All can be unified by these spheres and its rotations towards spherization I think .

Sincerely

Steve

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Nice links, thank you Lawrence and Mrs. Spice.

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Hi all ,

Yes indeed , thanks too Mrs Spice for those pictures of sizes ,always the spheres and spherization .

In my model ,The volume is very important in my quantum model and its entanglements of spheres .

Cordially

Steve

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In order to properly understand the notion of black holes and dark energy, the following newly published article is required reading:

The Dream Fundamentally Balances and Unifies Gravity and Electromagnetism

http://radicalacademy.com/studentrefphilfmd13.htm

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All of these discussions about Black Holes will be affected in the future since observational and theoretical evidence is developing in support of the existence of Magnetospheric Eternally Collapsing Objects (MECO) instead of Black Holes in Quasars (see attached paper published in Astronomical Journal).

Would anybody like to have a discussion with me on the topic of MECO vs Black Holes in quasars and AGN in the future?

Dr. Darryl Leiter

Visiting Scientist

NRAO

dleiter@nrao.edu

attachments: SLR_ASTR.J.v132pg4202006.pdf

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I looked at one of these papers briefly. I get the impression this involves gravitational energy and plasma heating. Time is a bit short, so it might be best if you could give a nutshell idea behind thie first.

L.C

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Hi Lawrence,

Thanks for looking at my papers and replying to my post.

The physics of a Magnetospheric Eternally Collapsing Object (MECO) involves a general relativitivistic collapse which includes quantum electrodynamic plasma heating and magnetic compression processes which generate an Eddington limited balance inside of the photon orbit but outside of the event horizon of a gravitationally collapsing object.

Astrophysically such a highly redshiftd compact MECOCobject would not have an event horizon but still look a lot like a black hole. The main difference would be that a MECO would have an intrinsic magnetic moment which could interact with its accretion disk enviroment and produce observable effects which a black hole could not. Such is the case with

the observations associated with the quasar Q0957.

A brief summary of the basic physical ideas underlying the MECO solutions to the Einstein-Maxwell equations are contained in the attached documents. The first is a one page description of the physics involved. The second is a oopy of a seminar given on the topic at Harvard CFa in 2008. After you look them over I would be happy to answer any questions that you would like to ask.

Thanks again for your interest.

Darryl Leiter

attachments: MECO_AND_THE_STRONG_PRINCIPLE_OF_EQUIVALENCE.pdf

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Hi Lawrence,

In regard to the above post the second attachment (2008 MECO SEMINAR GIVEN AT HARVARD CFA) did not go thru so I am sending it again in a different form.

Darryl Leiter

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